Reproducing/recording apparatus

ABSTRACT

A playback unit ( 3 ) reproduces contents which are recorded on a video cassette tape ( 2 ), and a recording unit ( 6 ) records the contents on another video cassette tape ( 7 ) and, simultaneously, an erasing unit ( 5 ) erases the contents from the video cassette tape ( 2 ). 
     Thereby, the copy-inhibited contents recorded on the video cassette tape ( 2 ) can be transferred to the other video cassette tape ( 7 ) without copying the contents.

FIELD OF INVENTION

The present invention relates to playback of contents recorded on astorage medium, and recording and erasing of the contents on/from thestorage medium and, more particularly, to a playback/recording apparatuswhich transfers copy-inhibited contents recorded on a storage medium toanother storage medium while erasing the contents from the storagemedium.

BACKGROUND OF THE INVENTION

In a conventional playback/recording apparatus, for example,copy-inhibited contents which are digital-recorded on a storage mediumare hand Led such that copyright information thereof is detected, andonly playback of the contents is carried out.

Furthermore, in the conventional playback/recording apparatus, withrespect to copy-inhibited contents which are analog-recorded on a videocassette tape, even when a reproduced signal thereof is recorded onanother video cassette tape, a reproduced image thereof is degraded inimage quality by the effect of an analog protection system, whichresults in an image the viewer cannot view normally, whereby illegalcopying is avoided.

For example, Japanese Published Patent Application No. Hei.9-130766proposes methods of transferring and recording television signals and arecording apparatus, which will be described as a specific example of aprior art, with reference to FIG. 15. FIG. 15 is a diagram illustratinga signal format for transferring copy generation restrictioninformation.

In the signal format, CGMS information is superimposed by utilizing aformat of an extended data service (XDS) signal which is standardized inrelation to a closed caption signal that is superimposed on the 21stline in a vertical blanking period of an analog television signal. TheXDS signal is composed of a clock run-in period, a start bit, and adigital signal of 16 bits, and the digital signal is divided into twobytes for characters 1 and 2. The information based on the standard ofthe XDS signal and the CGMS information can be distinguished from eachother by the start bit, and the character 1 and/or the character 2,whereby the recording apparatus identifies the CGMS information on the21st line, and performs copy generation restriction.

As described above, with respect to copying of contents, theconventional playback/recording apparatus performs copying when thecontents are not copyinhibited, and performs only playback when thecontents are copy-inhibited. Further, it performs copy generationrestriction on the basis of the copy generation restriction information.

Accordingly, for example, the viewer cannot transfer copy-inhibitedcontents recorded on an analog tape, to a digital tape for editing.

That is, an apparatus which is able to appropriately perform transfer ofcontents protected by copyright, has not yet been developed.

SUMMARY OF INVENTION

The present invention is made to solve the above-described problems andhas for its object to provide a playback/recording apparatus which isable to perform transfer of contents recorded on a storage medium toanother storage medium while erasing the contents from the originalstorage medium, when the contents are copy-inhibited.

According to claim 1 of the present invention, there is provided aplayback/recording apparatus for performing transfer of contentsrecorded on an erasable storage medium, and the apparatus comprises: aplayback means for reproducing contents recorded on a first storagemedium, and outputting the contents; a detection means for detectingcopyright information of the contents; an erasing means for erasing thecontents from the first storage medium; and a recording means forrecording the contents on a second storage medium; wherein, whenperforming transfer of the contents, the contents are reproduced by theplayback means and outputted and, when the output of the detection meansindicates that the contents are copy-inhibited, the contents are erasedfrom the first storage medium by the erasing means and, simultaneously,the contents are recorded on the second storage medium by the recordingmeans, thereby transferring the contents.

Therefore, when the copyright information of the contents recorded onthe storage medium is “copy-inhibited”, the contents on which a copyinhibition measurement is performed are erased from the storage mediumwhen the storage medium is an erasable medium and, simultaneously, thecontents which include the copyright information indicating“copy-inhibited” and are subjected to the copy inhibition measurementare recorded on another storage medium, whereby transfer of the contentscan be carried out while avoiding that the same contents exist at thesame time.

According to claim 2 of the present invention, there is provided aplayback/recording apparatus for performing transfer of contentsrecorded on an erasable storage medium, and the apparatus comprises: aplayback means for reproducing contents recorded on a first storagemedium, and outputting the contents; a detection means for detectingcopyright information of the contents; an erasing means for erasing thecontents from the first storage medium; an encryption means forencrypting the output of the playback means, and outputting theencrypted data; a temporary storage means for temporarily storing theencrypted data; a decryption means for decrypting the encrypted data;and a recording means for recording the contents on a second storagemedium; wherein, when performing transfer of the contents, the contentsare reproduced by the playback means and outputted and, when the outputof the detection means indicates that the contents are copy-inhibited,the contents are erased from the first storage medium by the erasingmeans and, simultaneously, the contents are encrypted by the encryptionmeans and temporarily stored in the temporary storage means and, afterthe erasing is ended, the encrypted data stored in the temporary storagemeans are read and outputted, and the encrypted data are decrypted bythe decryption means and outputted and, further, the encrypted datastored in the temporary storage means are erased, and the decryptedcontents are recorded on the second storage medium by the recordingmeans, thereby transferring the contents.

Therefore, when the case where the copyright information of the contentsrecorded on the storage medium is “copy-inhibited”, the contents onwhich a copy inhibition measurement is performed are erased from thestorage medium and simultaneously stored in the temporary storage meanswhen the storage medium is an erasable medium, and thereafter, thecontents which include the copyright information indicating“copy-inhibited” and are subjected to the copy inhibition measurementare recorded on another storage medium, whereby transfer of the contentscan be carried out while avoiding that the same contents exist at thesame time.

According to claim 3 of the present invention, there is provided aplayback/recording apparatus for performing transfer of contentsrecorded on an erasable storage medium between apparatuses, andcomprising a playback/erasing apparatus as a first apparatus, arecording apparatus as a second apparatus, and a transmission line suchas a transmission cable or the like for connecting the first and secondapparatuses; the first apparatus comprising: a first authenticationmeans for performing mutual authentication with the second apparatus,and transfer of contents including transfer information which indicatestransfer of the contents, or the like, between itself and the secondapparatus; a playback means for reproducing contents recorded on a firststorage medium, and outputting the reproduced contents; a detectionmeans for detecting copyright information of the contents; an erasingmeans for erasing the contents from the first storage medium; and ananalog protection system (APS) for incorporating analog protection, thetransfer information, and the like into the output of the playbackmeans; and the second apparatus comprising: a second authenticationmeans for performing mutual authentication with the first apparatus, andtransfer of the contents including the transfer information, betweenitself and the first apparatus; and a recording means for recording thecontents on a second storage medium; wherein, when performing transferof the contents, mutual authentication is carried out between the firstauthentication means and the second authentication means, and thecontents are reproduced by the playback means and outputted and, whenthe output of the detection means indicates that the contents arecopy-inhibited, the analog protection, the transfer information, and thelike are incorporated into the output of the playback means by the APS,and the contents are erased from the first storage medium by the erasingmeans and, simultaneously, the transfer information is detected by thesecond authentication means, and the contents are recorded on the secondstorage medium by the recording means on the basis of the transferinformation, thereby transferring the contents.

Therefore, when the copyright information of the contents recorded onthe storage medium is “copy-inhibited”, the contents on which a copyinhibition measurement is performed are erased from the storage mediumwhen the storage medium is an erasable medium, and the transferinformation is assigned to vacant bits of CGMS information andanalog-transferred between the apparatuses, and the contents whichinclude the copyright information indicating “copy-inhibited” and aresubjected to the copy inhibition measurement are recorded on anotherstorage medium, whereby transfer of the contents can be carried outwhile avoiding that the same contents exist at the same time.

According to claim 4 of the present invention, in the playback/recordingapparatus defined in claim 3, information such as the transferinformation indicating transfer of the contents exists in a verticalblanking period of a video signal.

Therefore, the contents are made to have the transfer information,whereby the contents can be analog-transferred between the apparatuseswhich have performed mutual authentication.

According to claim 5 of the present invention, in the playback/recordingapparatus defined in claim 3, the second storage medium is a videocassette tape; and an analog protection signal is superimposed andrecorded on the contents.

Therefore, the contents which have been transferred to another videocassette tape can be subjected to copy protection. playback/recordingapparatus for performing transfer of contents recorded on an erasablestorage medium between apparatuses, and comprising a playback/erasingapparatus as a first apparatus, a recording apparatus as a secondapparatus, and a transmission line such as a transmission cable or thelike for connecting the first and second apparatuses; the firstapparatus comprising: a first authentication means for performing mutualauthentication and transfer of contents between itself and the secondapparatus; a playback means for reproducing contents recorded on a firststorage medium, and outputting the reproduced contents; a detectionmeans for detecting copyright information of the contents; an erasingmeans for erasing the contents from the first storage medium; and anencryption means for encrypting the output from the playback means, andoutputting the encrypted data; and the second apparatus comprising: asecond authentication means for performing mutual authentication andtransfer of contents between itself and the first apparatus; adecryption means for decrypting the encrypted data; and a recordingmeans for recording the contents on a second storage means; wherein,when performing transfer of the contents, mutual authentication iscarried out between the first authentication means and the secondauthentication means, the contents are reproduced by the playback meansand outputted and, when the output of the detection means indicates thatthe contents are copy-inhibited, data of the contents are encrypted bythe encryption means and outputted, the contents are erased from thefirst storage medium by the erasing means, the encrypted data aredecrypted by the decryption means and outputted, and the contents arerecorded on the second storage means by the recording means, therebytransferring the contents.

Therefore, when the copyright information of the contents recorded onthe storage medium is “copy-inhibited”, the contents on which a copyinhibition measurement is performed are erased from the storage mediumwhen the storage medium is an erasable medium, and the contents areencrypted and digital-transferred together with the transfer informationbetween the apparatuses which have performed mutual authentication and,after the contents are decrypted, the contents which include thecopyright information indicating “copy-inhibited” and are subjected tothe copy inhibition measurement are recorded on another storage medium,whereby transfer of the contents can be carried out while avoiding thatthe same contents exist at the same time.

According to claim 7 of the present invention, there is provided aplayback/recording apparatus for performing transfer of contentsrecorded on an erasable storage medium between apparatuses, andcomprising a playback/erasing apparatus as a first apparatus, arecording apparatus as a second apparatus, and a transmission line suchas a transmission cable or the like for connecting the first and secondapparatuses; the first apparatus comprising: a first authenticationmeans for performing mutual authentication with the second apparatus,and transfer of contents including transfer information which indicatestransfer of the contents, or the like, between itself and the secondapparatus; a playback means for reproducing contents recorded on a firststorage medium, and outputting the reproduced contents; a detectionmeans for detecting copyright information of the contents; an erasingmeans for erasing the contents from the first storage medium; acompression means for compressing image data of the contents, andoutputting the compressed data; and an encryption means for encryptingthe output from the playback means, and outputting the encrypted data;and the second apparatus comprising: a second authentication means forperforming mutual authentication with the first apparatus, and transferof contents including transfer information which indicates transfer ofthe contents, or the like, between itself and the first apparatus; adecryption means for decrypting the encrypted data; a decompressionmeans for decompressing the compressed data; and a recording means forrecording the contents on a second storage means; wherein, whenperforming transfer of the contents, mutual authentication is carriedout between the first authentication means and the second authenticationmeans, the contents are reproduced by the playback means and outputtedand, when the output of the detection means indicates that the contentsare copy-inhibited, image data of the contents are compressed by thecompression means and, simultaneously, additional information such asthe copyright information, the transfer information and the like areinserted in an area which is secured by the compression, the data of thecontents are encrypted by the encryption means and outputted, thecontents are erased from the first storage medium by the erasing meansand, when the additional information including the transfer informationis detected by the second authentication means, the encrypted data aredecrypted by the decryption means, the compressed data are decompressedby the decompression means to output the image data, and the contentsare recorded on the second storage means by the recording means, therebytransferring the contents.

Therefore, when the copyright information of the contents recorded onthe storage medium is “copy-inhibited”, the contents on which a copyinhibition measurement is performed are erased from the storage mediumwhen the storage medium is an erasable medium, and the uncompresseddigital image data included in the contents are compressed so that theadditional information including the transfer information of thecontents can be added, and thereafter, the compressed data areencrypted, digital-transferred between the apparatuses which haveperformed mutual authentication, decrypted, and decompressed, andthereafter, the contents which include the copyright informationindicating “copy-inhibited” and are subjected to the copy inhibitionmeasurement are recorded on another storage medium, whereby transfer ofthe contents can be carried out while avoiding that the same contentsexist at the same time.

According to claim 8 of the present invention, in the playback/recordingapparatus defined in claim 7, the compression means is a means forcompressing data by reducing a total number T of unused generated valueswhich are smaller than a generated value G; the generated value G is avalue which is generated by arranging plural data values so as to havedigits, among data where the total number of data values to be used asdata values within the contents is less than the total number of valuesexpressed by a number of bits per data value, i.e., among data havingvalues not to be used as data values; the unused generated values arevalues which include the unused data values and are generated byarranging plural data values so as to have digits; and the plural datavalues are made tc, have the same number of digits by adding 0 untilreaching a number of digits of a maximum data value.

Therefore, an area, where the additional information inchlding thetransfer information of the contents is to be inserted, can be secured,whereby the contents can be transferred without increasing the transferrate.

According to claim 9 of the present invention, in the playback/recordingapparatus defined in claim 7, the decompression means is a means fordecompressing the compressed data by calculating the total number T ofunused generated values which are smaller than a generated value G, andadding it to the generated value G; the generated value G is a valuewhich is generated by arranging plural data values so as to have digits,among data where the total number of data values to be used as datavalues within the contents is less than the total number of valuesexpressed by a number of bits per data value, i.e., among data havingvalues not to be used as data values; the unused generated values arevalues which include the unused data values and are generated byarranging plural data values so as to have digits; and the plural datavalues are made to have the same number of digits by adding 0 untilreaching a number of digits of a maximum data value.

Therefore, the compressed digital data can be decompressed to restorethe original digital data.

According to claim 10 of the present invention, there is provided aplayback/erasing apparatus as a first apparatus, which is one ofcomponents of a playback/recording apparatus for performing transfer ofcontents recorded on an erasable storage medium, between the firstapparatus and a second apparatus, and the playback/erasing apparatuscomprises: a first authentication means for performing mutualauthentication and transfer of contents between itself and the secondapparatus; a playback means for reproducing contents recorded on a firststorage medium, and outputting the reproduced contents; a detectionmeans for detecting copyright information of the contents; and anerasing means for erasing the contents from the first storage medium;wherein, when performing transfer of the contents, mutual authenticationis carried out between the first authentication means and the secondapparatus, and the contents are reproduced by the playback means andoutputted and, when the output of the detection means indicates that thecontents are copy-inhibited, the contents are erased from the firststorage medium by the erasing means.

Therefore, when the contents recorded on the storage medium arecopy-inhibited, the contents are erased from the storage medium when thestorage medium is an erasable medium, and transferred to an externalapparatus which has performed mutual authentication, whereby thecontents can be transferred while avoiding that the same contents existat the same time.

According to claim 11 of the present invention, there is provided aplayback/erasing apparatus as a first apparatus, which is one ofcomponents of a playback/recording apparatus for performing transfer ofcontents recorded on an erasable storage medium, between the firstapparatus and a second apparatus, and the playback/erasing apparatuscomprises: a first authentication means for performing mutualauthentication with the second apparatus, and transfer of contentsincluding transfer information which indicates transfer of the contents,or the like, between itself and the second apparatus; a playback meansfor reproducing contents recorded on a first storage medium, andoutputting the reproduced contents; a detection means for detectingcopyright information of the contents; an erasing means for erasing thecontents from the first storage medium; and an analog protection system(APS) for incorporating analog protection and the transfer informationor the like into the output of the playback means; wherein, whenperforming transfer of the contents, mutual authentication is carriedout between the first authentication means and the second apparatus, andthe contents are reproduced by the playback means and outputted and,when the output of the detection means indicates that the contents arecopy-inhibited, the analog protection and the transfer information orthe like are incorporated into the output of the playback means by theAPS, and the contents are erased from the first storage medium by theerasing means.

Therefore, when the contents recorded on the storage medium arecopy-inhibited, the contents are erased from the storage medium when thestorage medium is an erasable medium, and the transfer information isassigned to vacant bits of CGMS information and the APS is incorporatedinto the contents, and the contents can be analog-transferred to anexternal apparatus with which the first apparatus has performed mutualauthentication, whereby the contents can be transferred while avoidingthat the same contents exist at the same time.

According to claim 12 of the present invention, in the playback/erasingapparatus as the first apparatus defined in claim 11, the informationsuch as transfer information indicating transfer of the contents existsin a vertical blanking period of a video signal.

Therefore, the contents are made to have the transfer information, andthe contents can be analog-transferred to an external apparatus whichhas performed mutual authentication.

According to claim 13 of the present invention, there is provided aplayback/erasing apparatus as a first apparatus, which is one ofcomponents of a playback/recording apparatus for performing transfer ofcontents recorded on an erasable storage medium, between the firstapparatus and a second apparatus, and the playback/erasing apparatuscomprises: a first authentication means for performing mutualauthentication and transfer of contents between itself and the secondapparatus; a playback means for reproducing contents recorded on a firststorage medium, and outputting the reproduced contents; a detectionmeans for detecting copyright information of the contents; an erasingmeans for erasing the contents from the first storage medium; and anencryption means for encrypting the output of the playback means, andoutputting the encrypted data; wherein, when performing transfer of thecontents, mutual authentication is carried out between the firstauthentication means and the second apparatus, and the contents arereproduced by the playback means and outputted and, when the output ofthe detection means indicates that the contents are copy-inhibited, thedata of the contents are encrypted by the encryption means andoutputted, and the contents are erased from the first storage medium bythe erasing means.

Therefore, when the contents recorded on the storage medium arecopy-inhibited, the contents are erased from the storage medium when thestorage medium is an erasable medium, and the contents are encrypted anddigital-transferred together with the transfer information to anexternal apparatus which has performed mutual authentication, wherebythe contents can be transferred while avoiding that the same contentsexist at the same time.

According to claim 14 of the present invention, there is provided aplayback/erasing apparatus as a first apparatus, which is one ofcomponents of a playback/recording apparatus for performing transfer ofcontents recorded on an erasable storage medium, between the firstapparatus and a second apparatus, and the playback/erasing apparatuscomprises: a first authentication means for performing mutualauthentication with the second apparatus, and transfer of contentsincluding transfer information which indicates transfer of the contents,or the like, between itself and the second apparatus; a playback meansfor reproducing contents recorded on a first storage medium, andoutputting the reproduced contents; a detection means for detectingcopyright information of the contents; an erasing means for erasing thecontents from the first storage medium; a compression means forcompressing image data of the contents, and outputting the compresseddata; and an encryption means for encrypting the output of the playbackmeans, and outputting the encrypted data; wherein, when performingtransfer of the contents, mutual authentication is carried out betweenthe first authentication means and the second apparatus, and thecontents are reproduced by the playback means and outputted and, whenthe output of the detection means indicates that the contents arecopy-inhibited, the image data of the contents are compressed by thecompression means and additional information such as the copyrightinformation, the transfer information and the like are inserted in anarea which is secured by the compression, the data of the contents areencrypted by the encryption means and outputted, and the contents areerased from the first storage medium by the erasing means.

Therefore, when the contents recorded on the storage medium arecopy-inhibited, the contents are erased from the storage medium when thestorage medium is an erasable medium, and the uncompressed digital imagedata included in the contents are compressed so that the additionalinformation including the transfer information of the contents can beadded, and thereafter, the contents are encrypted anddigital-transferred to an external apparatus which has performed mutualauthentication, whereby transfer of the contents can be carried outwhile avoiding that the same contents exist at the same time.

According to claim 15 of the present invention, in the playback/erasingapparatus as the first apparatus defined in claim 14, the compressionmeans is a means for compressing data by reducing a total number T ofunused generated values which are smaller than a generated value G; thegenerated value G is a value which is generated by arranging plural datavalues so as to have digits, among data where the total number of datavalues to be used as data values within the contents is less than thetotal number of values expressed by a number of bits per data value,i.e., among data having values not to be used as data values; the unusedgenerated values are values which include the unused data values and aregenerated by arranging plural data values so as to have digits; and theplural data values are made to have the same number of digits by adding0 until reaching a number of digits of a maximum data value.

Therefore, an area, where the additional information including thetransfer information of the contents is to be inserted, can be secured,whereby the contents can be transferred without increasing the transferrate.

According to claim 16 of the present invention, there is provided arecording apparatus as a second apparatus, which is one of components ofa playback/recording apparatus for performing transfer of contentsrecorded on an erasable storage medium between a first apparatus and thesecond apparatus, and the recording apparatus comprises: a secondauthentication means for performing mutual authentication with the firstapparatus, and transfer of contents including transfer information whichindicates transfer of the contents, or the like, between itself and thefirst apparatus; and a recording means for recording the contents on asecond storage medium; wherein, when performing transfer of thecontents, mutual authentication is carried out between the secondauthentication means and the first apparatus, the transfer informationis detected by the second authentication means, and the contents arerecorded on the second storage means by the recording means on the basisof the transfer information.

Therefore, the copy-inhibited contents transferred from an externalapparatus which has performed mutual authentication, which contentsinclude the copyright information indicating “copy-inhibited” and aresubjected to the copy inhibition measurement, can be transferred toanother storage medium, whereby transfer of the contents can be carriedout while avoiding that the same contents exist at the same time.

According to claim 17 of the present invention, in the recordingapparatus as the second apparatus defined in claim 16, the secondstorage medium is a video cassette tape, and an analog protection signalis superimposed and recorded on the contents.

Therefore, the contents which have been transferred to another videocassette tape can be subjected to copy protection.

According to claim 18 of the present invention, there is provided arecording apparatus as a second apparatus, which is one of components ofa playback/recording apparatus for performing transfer of contentsrecorded on an erasable storage medium between a first apparatus and thesecond apparatus, and the recording apparatus comprises: a secondauthentication means for performing mutual authentication and transferof contents between itself and the first apparatus; a decryption meansfor decrypting encrypted data; and a recording means for recording thecontents on a second storage medium; wherein, when performing transferof the contents, mutual authentication is carried out between the secondauthentication means and the first apparatus, encrypted data aredecrypted by the decryption means and outputted, and the contents arerecorded on the second storage means by the recording means.

Therefore, after the encrypted contents transferred from an externalapparatus which has performed mutual authentication are decrypted, thecontents which include the copyright information indicating“copy-inhibited” and are subjected to a copy inhibition measurement canbe recorded on another storage medium, whereby transfer of the contentscan be carried out while avoiding that the same contents exist at thesame time.

According to claim 19 of the present invention, there is provided arecording apparatus as a second apparatus, which is one of components ofa playback/recording apparatus for performing transfer of contentsrecorded on an erasable storage medium between a first apparatus and thesecond apparatus, and the recording apparatus comprises: a secondauthentication means for performing mutual authentication with the firstapparatus, and transfer of contents including transfer information whichindicates transfer of the contents, or the like, between itself and thefirst apparatus; a decompression means for decompressing compresseddata; and a recording means for recording the contents on a secondstorage medium; wherein, when performing transfer of the contents,mutual authentication is carried out between the second authenticationmeans and the first apparatus and, when additional information includingthe transfer information and the like is detected by the secondauthentication means, encrypted data are decrypted by the decryptionmeans and outputted, compressed data are decompressed by thedecompression means to output the contents, and the contents arerecorded on the second storage means by the recording means.

Therefore, after the compressed and encrypted contents transferred froman external apparatus which has performed mutual authentication aredecrypted and decompressed, the contents which include the copyrightinformation indicating “copy-inhibited” and are subjected to a copyinhibition measurement can be recorded on another storage medium,whereby transfer of the contents can be carried out while avoiding thatthe same contents exist at the same time.

According to claim 20 of the present invention, in the recordingapparatus as the second apparatus defined in claim 19, the decompressionmeans is a means for decompressing the compressed data by calculatingthe total number T of unused generated values which are smaller than agenerated value G, and adding it to the generated value G; the generatedvalue G is a value which is generated by arranging plural data values soas to have digits, among data where the total number of data values tobe used as data values within the contents is less than the total numberof values expressed by a number of bits per data value, i.e., among datahaving values not to be used as data values; the unused generated valuesare values which include the unused data values and are generated byarranging plural data values so as to have digits; and the plural datavalues are made to have the same number of digits by adding 0 untilreaching a number of digits of a maximum data value.

Therefore, the compressed digital data can be decompressed to restorethe original digital data.

According to claim 21 of the present invention, the playback/recordingapparatus defined in claim 6 or 7 further comprises a temporary storagemeans for temporarily storing the contents; and the contents aretemporarily stored in the temporary storage means.

Therefore, the contents can be continuously transferred with efficiency.

According to claim 22 of the present invention, the playback/erasingapparatus as the first apparatus defined in claim 13 or 14 furthercomprises a temporary storage means for temporarily storing thecontents; and the contents are temporarily stored in the temporarystorage means.

Therefore, the contents can be continuously transferred with efficiency.

According to claim 23 of the present invention, the recording apparatusas the second apparatus defined in claim 18 or 19 further comprises atemporary storage means for temporarily storing the contents; and thecontents are temporarily stored in the temporary storage means.

Therefore, the contents can be continuously transferred with efficiency.

According to claim 24 of the present invention, the playback/recordingapparatus defined in claim 1 or 2 further comprises: a second playbackmeans for reproducing the contents recorded on the second storagemedium; and a control means for controlling the playback means or theerasing means, the second playback means, and the recording means;wherein the playback means or the erasing means, the second playbackmeans, and the recording means are controlled by the control means onthe basis of transfer information including information of collationbetween a recording signal to the second storage medium and a reproducedsignal from the second storage medium, or the like, thereby performingtransfer of the contents.

Therefore, the contents transfer process can be controlled byreproducing the data recorded on another storage medium and comparingthe recorded signal with the reproduced signal, whereby normal transferof the contents can be carried out.

According to claim 25 of the present invention, the playback/recordingapparatus defined in any of claims 3, 6, and 7 further comprises: asecond playback means for reproducing the contents recorded on thesecond storage medium; a first control means for controlling theplayback means and the erasing means; and a second control means forcontrolling the second playback means and the recording means; whereinthe playback means or the erasing means, the second playback means, andthe recording means are controlled by the first control means or thesecond control means, on the basis of transfer information includinginformation of collation between a recording signal to the secondstorage medium and a reproduced signal from the second storage medium,or the like, thereby performing transfer of the contents.

Therefore, the contents transfer process can be controlled between theapparatuses which have performed mutual authentication, by reproducingthe data recorded on another storage medium and comparing the recordedsignal with the reproduced signal, whereby normal transfer of thecontents can be carried out.

According to claim 26 of the present invention, the playback/erasingapparatus as the first apparatus defined in any of claims 10, 11, 13,and 14 further comprises a first control means for controlling theplayback means and the erasing means; and the playback means and theerasing means are controlled by the first control means, therebyperforming transfer of the contents.

Therefore, the contents transfer process can be controlled, and transferof the contents can be stopped.

According to claim 27 of the present invention, the recording apparatusas the second apparatus defined in any of claims 16, 18, and 19 furthercomprises: a second playback means for reproducing the contents recordedon the second storage means; and a second control means for controllingthe second playback means and the recording means; wherein the secondplayback means and the recording means are controlled by the secondcontrol means on the basis of transfer information including informationof collation between a recording signal to the second storage medium anda reproduced signal from the second storage medium, or the like, therebyperforming transfer of the contents.

Therefore, the contents transfer process can be controlled between theapparatuses which have performed mutual authentication, by reproducingthe data recorded on another storage medium and comparing the recordedsignal with the reproduced signal, whereby normal transfer of thecontents can be carried out.

According to claim 28 of the present invention, in theplayback/recording apparatus defined in any of claims 3, 6, and 7,mutual authentication by the first authentication means or the secondauthentication means is also carried out during transfer of thecontents, and the transfer of the contents is contimied when mutualauthentication is established.

Therefore, transfer of the contents can be carried out only whentransfer of the contents is permitted between the apparatuses which haveperformed mutual authentication.

According to claim 29 of the present invention, in the playback/erasingapparatus as the first apparatus defined in any of claims 10, 11, 13,and 14, mutual authentication by the first authentication means is alsocarried out during transfer of the contents, and the transfer of thecontents is continued when mutual authentication is established.

Therefore, the contents can be transferred to an external apparatuswhich has performed mutual authentication, only when transfer of thecontents is permitted.

According to claim 30 of the present invention, in the recordingapparatus as the second apparatus defined in any of claims 16, 18, and19, mutual authentication by the second authentication means is alsocarried out during transfer of the contents, and the transfer of thecontents is continued when mutual authentication is established.

Therefore, the contents transferred from an external apparatus which hasperformed mutual authentication, can be recorded only when transfer ofthe contents is permitted.

According to claim 31 of the present invention, in theplayback/recording apparatus defined in claim 25, the contents aredivided into plural sections, and transfer of the contents is carriedout in units of sections.

Therefore, transfer of the contents can be carried out with stability,in units of sections, between the apparatuses which have performedmutual authentication.

According to claim 32 of the present invention, in the playback/erasingapparatus as the first apparatus defined in claim 26, the contents aredivided into plural sections, and transfer of the contents is carriedout in units of sections.

Therefore, the contents can be transferred in units of sections, to anexternal apparatus which has performed mutual authentication.

According to claim 33 of the present invention, in the recordingapparatus as the second apparatus defined in claim 27, the contents aredivided into plural sections, and transfer of the contents is carriedout in units of sections.

Therefore, the contents transferred from an external apparatus which hasperformed mutual authentication, can be recorded in units of sections onanother storage medium.

According to claim 34 of the present invention, in theplayback/recording apparatus defined in claim 31, when performingtransfer of the contents, the recording position of the contents on thesecond storage medium matches the erasing position of the contents onthe first storage medium.

Therefore, transfer of copy-inhibited contents, such as a still picture,can be appropriately carried out between the apparatuses which haveperformed mutual authentication.

According to claim 35 of the present invention, in the playback/erasingapparatus as the first apparatus defined in claim 32, when performingtransfer of the contents, the erasing position of the contents on thefirst storage medium matches the recording position of the contents onthe second storage medium of the external apparatus.

Therefore, copy-inhibited contents, such as a still picture, can beappropriately transferred to an external apparatus which has performedmutual authentication.

According to claim 36 of the present invention, in the recordingapparatus as the second apparatus defined in claim 33, when performingtransfer of the contents, the recording position of the contents on thesecond storage medium matches the erasing position of the contents onthe first storage medium of the external apparatus.

Therefore, copy-inhibited contents, such as a still picture, transferredfrom an external apparatus which has performed mutual authentication,can be appropriately recorded.

According to claim 37 of the present invention, the playback/recordingapparatus defined in claim 24 further comprises a nonvolatile memory forrecording and holding information relating to contents transfer, such asthe transfer information or the copyright information, when transfer ofthe contents is carried out; and the transfer process is continued whenthe transfer information exists in the nonvolatile memory, and theinformation is erased when the transfer is ended, whereby, even when thecontents transfer process is interrupted clue to power off of theplayback/recording apparatus or the like, the transfer process can beresumed by reading the transfer information from the memory.

Therefore, even when transfer of the contents is interrupted during thetransfer, the transfer information can be obtained from the nonvolatilememory, whereby transfer of the contents can be resumed or continued.

According to claim 38 of the present invention, the playback/recordingapparatus defined in claim 25 further comprises a nonvolatile memory forrecording and holding information relating to contents transfer, such asthe transfer information or the copyright information, the informationindicating division of the contents, and the like, when transfer of thecontents is carried out; and the transfer process is continued when thetransfer information exists in the nonvolatile memory, and theinformation is erased when the transfer is ended, whereby, even when thecontents transfer process is interrupted due to power off of theplayback/recording apparatus or the like, the transfer process can beresumed by reading the transfer information from the memory.

Therefore, even when transfer of the contents is interrupted during thetransfer between the apparatuses which have performed mutualauthentication, the transfer information can be obtained from thenonvolatile memory, whereby transfer of the contents can be resumed orcontinued.

According to claim 39 of the present invention, the playback/erasingapparatus as the first apparatus defined in claim 26 further comprises anonvolatile memory for recording and holding information relating tocontents transfer, such as the transfer information or the copyrightinformation, the information indicating division of the contents, andthe like, when transfer of the contents is carried out; and the transferprocess is continued when the transfer information exists in thenonvolatile memory, and the information is erased when the transfer isended, whereby, even when the contents transfer process is interrupteddue to power off of the playback/recording apparatus or the like, thetransfer process can be resumed by reading the transfer information fromthe memory.

Therefore, even when transfer of the contents to an external apparatuswhich has performed mutual authentication is interrupted during thetransfer, the transfer information can be obtained from the nonvolatilememory, whereby transfer of the contents can be resumed or continued.

According to claim 40 of the present invention, the playback/recordingapparatus defined in claim 1 or 2 further comprises a transferinstruction means for sending an instruction for transferring thecontents, to the playback/recording apparatus; and transfer of thecontents is carried out according to the instruction of the transferinstruction means.

Therefore, the instruction for transferring the contents can be sent tothe playback/recording apparatus.

According to claim 41 of the present invention, the playback/recordingapparatus defined in any of claims 3, 6, and 7 further comprises atransfer instruction means for sending an instruction for transferringthe contents, to the first apparatus; and transfer of the contents iscarried out according to the instruction of the transfer instructionmeans.

Therefore, the instruction for transferring the contents can be sent tothe first apparatus in the playback/recording apparatus.

According to claim 42 of the present invention, the playback/erasingapparatus as the first apparatus defined in any of claims 10, 11, 13,and 14 further comprises a transfer instruction means for sending aninstruction for transferring the contents, to the first apparatus; andtransfer of the contents is carried out according to the instruction ofthe transfer instruction means.

Therefore, the instruction for transferring the contents can be sent tothe first apparatus.

According to claim 43 of the present invention, the playback/recordingapparatus defined in claim 1 or 2 further comprises a transfer displaymeans for displaying whether the contents are being transferred or not;and., when the contents are being transferred, it is displayed by thetransfer display means for the outside of the apparatus.

Therefore, the playback/recording apparatus can notify the viewer thatthe contents are being transferred.

According to claim 44 of the present invention, in theplayback/recording apparatus defined in any of claims 3, 6, and 7, thefirst apparatus is provided with a transfer display means for displayingwhether the contents are being transferred or not; and, when thecontents are being transferred, it is displayed by the transfer displaymeans for the outside of the apparatus.

Therefore, the playback/recording apparatus can notify the viewer thatthe contents are being transferred to an external apparatus which hasperformed mutual authentication.

According to claim 45 of the present invention, the playback/erasingapparatus as the first apparatus defined in any of claims 10, 11, 13,and 14 further comprises a transfer display means for displaying whetherthe contents are being transferred or not; and, when the contents arebeing transferred, it is displayed by the transfer display means for theoutside of the apparatus.

Therefore, the playback/recording apparatus can notify the viewer thatthe contents are being transferred to an external apparatus which hasperformed mutual authentication.

According to claim 46 of the present invention, there is provided astorage medium or a removable storage medium having informationindicating whether transfer of contents is permitted or not, on whichtransfer of contents is carried out by the playback/recording apparatus,or the playback/erasing apparatus as the first apparatus, or therecording apparatus as the second apparatus, which is defined in any ofclaims 1 to 45.

Therefore, transfer of the contents can be controlled by detectinginformation which indicates whether transfer of the contents ispermitted or not, or information which indicates whether transfer of thecontents is permitted or not according to a difference in media types orstorage modes between the transmitter and the receiver.

According to claim 47 of the present invention, there is provided aplayback/erasing apparatus as a first apparatus in a playback/recordingapparatus having a compression means for compressing data by reducing atotal number T of unused generated values which are smaller than agenerated value G; the generated value G is a value which is generatedby arranging plural data values so as to have digits, among data wherethe total number of data values to be used as data values within thecontents is less than the total number of values expressed by a numberof bits per data value, i.e., among data having values not to be used asdata values; the unused generated values are values which include theunused data values and are generated by arranging plural data values soas to have digits; the plural data values are made to have the samenumber of digits by adding 0 until reaching a number of digits of amaximum data value; and a data area is secured by the data compressionof the compression means so as to perform insertion of additionalinformation such as copyright information and transfer information, orthe like.

Therefore, an area, where the additional information including thetransfer information of the contents is to be inserted, can be secured,whereby the contents can be transferred without increasing the transferrate.

According to claim 48 of the present invention, there is provided arecording apparatus as a second apparatus in a playback/recordingapparatus having a decompression means for decompressing compressed databy calculating the total number T of unused generated values which aresmaller than a generated value G, and adding it to the generated valueG; the generated value G is a value which is generated by arrangingplural data values so as to have digits, among data where the totalnumber of data values to be used as data values within the contents isless than the total number of values expressed by a number of bits perdata value, i.e., among data having values not to be used as datavalues; the unused generated values are values which include the unuseddata values and are generated by arranging plural data values so as tohave digits; the plural data values are made to have the same number ofdigits by adding 0 until reaching a number of digits of a maximum datavalue; and the compressed data are decompressed by the decompressionmeans.

Therefore, the compressed digital data can be decompressed to restorethe original data.

According to claim 49 of the present invention, in theplayback/recording apparatus defined in claim 31, division of thecontents is performed by periodic counting of time which is possessed bythe playback/recording apparatus, when the first storage medium is avideo cassette tape; and it is performed in byte units of the contentsstored in the first storage medium, when the first storage medium is amagnetic disk, an optical disk, a magneto-optic disk, or the like.

Therefore, the contents can be divided into plural sections, and thecontents can be transferred in units of sections between the apparatuseswhich have performed mutual authentication.

According to claim 50 of the present invention, in the playback/erasingapparatus as the first apparatus defined in claim 32, division of thecontents is performed by periodic counting of time which is possessed bythe playback/erasing apparatus, when the first storage medium is a videocassette tape; and it is performed in byte units of the contents storedin the first storage medium, when the first storage medium is a magneticdisk, an optical disk, a magneto-optic disk, or the like.

Therefore, the contents can be divided into plural sections, and thecontents can be transferred in units of sections to an externalapparatus which has performed mutual authentication.

According to claim 51 of the present invention, in the recordingapparatus as the second apparatus defined in claim 33, division of thecontents is performed by periodic counting of time which is possessed bythe recording apparatus, when the second storage medium is a videocassette tape; and it is performed in byte units of the contents storedin the first storage medium, when the first storage medium is a magneticdisk, an optical disk, a magneto-optic disk, or the like.

Therefore, the contents can be divided into plural sections, and thecontents transferred from an external apparatus which has performedmutual authentication can be recorded in units of sections on anotherstorage medium.

The playback/recording apparatus according to the present invention isuseful as means for transferring copy-inhibited contents recorded on astorage medium to another storage medium without copying it.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram illustrating a playback/recording apparatusaccording to a first embodiment of the present invention.

FIG. 2 is a block diagram illustrating a playback/recording apparatusaccording to a second embodiment of the present invention.

FIG. 3 is a block diagram illustrating a playback/recording apparatusaccording to a third embodiment of the present invention.

FIG. 4 is a block diagram illustrating an APS in the playback/recordingapparatus according to the third embodiment of the present invention.

FIG. 5 is a waveform diagram illustrating CGMS information according tothe third embodiment of the present invention.

FIG. 6 is a block diagram illustrating a playback/recording apparatusaccording to a sixth embodiment of the present invention.

FIG. 7 is a block diagram illustrating an MPEG coding unit in theplayback/recording apparatus according to the fourth embodiment of thepresent invention.

FIG. 8 is a block diagram illustrating a playback/recording apparatusaccording to a fifth embodiment of the present invention.

FIG. 9 is a diagram illustrating computational expressions for datacompression according to the fifth embodiment of the present invention.

FIG. 10 is a block diagram illustrating a compression unit in theplayback/recording apparatus according to the fifth embodiment of thepresent invention.

FIG. 11 is a diagram illustrating computational expressions for datadecompression according to the fifth embodiment of the presentinvention.

FIG. 12 is a block diagram illustrating a decompression unit in theplayback/recording apparatus according to the fifth embodiment of thepresent invention.

FIG. 13 is a block diagram illustrating a playback/recording apparatusaccording to the sixth embodiment of the present invention.

FIG. 14 is a block diagram illustrating a playback/recording apparatusaccording to a seventh embodiment of the present invention.

FIG. 15 is a diagram illustrating a signal format for transferring CGMSinformation according to the prior art.

DETAILED DESCRIPTION OF THE INVENTION

Hereinafter, a first embodiment of the present invention will bedescribed.

Initially, the structure of a playback/recording apparatus according tothe first embodiment will be described with reference to FIG. 1. FIG. 1is a block diagram illustrating a playback/recording apparatus accordingto the first embodiment. In the figure, a playback/recording apparatus 8is composed of an erasable video cassette tape 2 on which contents arerecorded, a video cassette tape 7 to which the contents are to betransferred, a playback unit 3, a copyright information detection unit4, an erasing unit 5, and a recording unit 6. When the apparatusreceives an instruction for transferring the contents, from a remotecontroller 1 which is a transfer instruction means, the apparatustransfers the contents recorded on the erasable video cassette tape 2 toanother video cassette tape 7.

The playback unit 3 reproduces the contents recorded on the videocassette tape 2, and outputs an audio signal and a video signal.

The copyright information detection unit 4 detects copyright informationof the contents.

When the copyright information detection unit 4 detects that thecontents are copy-inhibited, the recording unit 6 superimposes a signalon the video signal which is reproduced by the playback unit 3 and,thereafter, records the video signal as well as the audio signal on thevideo cassette tape 7.

The erasing unit 5 erases the contents reproduced by the playback unit3.

Next, a description will be given of the operation of theplayback/recording apparatus according to the first embodiment.

When the playback/recording apparatus 8 receives an instruction fortransferring the contents, from the remote controller 1, the playbackunit 3 reproduces the contents recorded on the erasable video cassettetape 2, and outputs the audio signal and the video signal to thecopyright information detection unit 4. The copyright informationdetection unit 4 detects whether the contents are subjected to analogprotection or not, from the video signal supplied from the playback unit3. In this detection, the detection unit 4 observes the verticalblanking period of the video signal, and decides that the contents arecopy-inhibited when there is a pseudo sync pulse that causes an AGC ofthe recording unit 6 to malfunction.

When the copyright information detection unit 4 decides that thecontents recorded on the video cassette tape 2 are copy-inhibited, therecording unit 6 detects that the contents are copy-inhibited from theoutput of the copyright information detection unit 4, and superimposesan analog protection signal detected by the copyright informationdetection unit 4 on the video signal outputted from the playback unit 3and, further, records the video signal together with the audio signal onthe video cassette tape 7, under the state where, for copy protection,setting is changed to a time constant of the AGC, which is not affectedby the analog protection signal. Further, the erasing unit immediatelyerases the signal reproduced by the playback unit 3, from the videocassette tape 2.

As described above, in the playback/recording apparatus according to thefirst embodiment, when the copyright information of the contents whichare analog-recorded on the erasable video cassette tape 2 is“copy-inhibited”, the contents which include the copyright informationindicating “copy-inhibited” and are in the copy-inhibited state areerased from the video cassette tape and, simultaneously, the contentsare recorded on the other video cassette tape 7. Therefore, thecopy-inhibited contents which are analog-recorded on the video cassettetape 2 can be transferred to the other video cassette tape 7 whilepreventing that the same contents exist at the same time.

Hereinafter, a second embodiment of the present invention will bedescribed.

Initially, the structure of a playback/recording apparatus according tothe second embodiment will be described with reference to FIG. 2.

FIG. 2 is a block diagram of a playback/recording apparatus according tothe second embodiment. In FIG. 2, a playback/recording apparatus 8 iscomposed of an erasable video cassette tape 2 on which contents arerecorded, a video cassette tape 7 to which the contents are to betransferred, a copyright information detection unit 4, an erasing unit5, a digital signal playback unit 9, an encryption unit 10, an HDD (harddisk drive) 11, a decryption unit 12, and a digital signal recordingunit 13. When the apparatus 8 receives an instruction for transferringthe contents, from a remote controller 1 which is a transfer instructionmeans, the apparatus 8 transfers the contents recorded on the erasablevideo cassette tape 2 to another video cassette tape 7. The sameconstituents as those of the above-described embodiment are given thesame reference numerals and, therefore, descriptions thereof will beomitted hereinafter.

The digital signal playback unit 9 reproduces an MPEG stream which isdigital-recorded on the erasable video cassette tape 2.

The encryption unit 10 encrypts the MPEG stream reproduced by thedigital signal playback unit 9, and outputs the encrypted MPEG stream.

The HDD 11 temporarily stores the MPEG stream encrypted by theencryption unit 10.

The decryption unit 12 decrypts the encrypted MPEG stream from the HDD11, and outputs the decrypted MPEG stream. At this time, the HDD 11outputs the MPEG stream to the decryption unit 12 and, simultaneously,erases the data.

The digital signal recording unit 13 digital-records the MPEG streamoutputted from the decryption unit 12, on the video cassette tape 7.

Next, the operation of the playback/recording apparatus according to thesecond embodiment will be described.

When the playback/recording apparatus 8 receives an instruction fortransferring the contents, from the remote controller 1, the digitalsignal playback unit 9 reproduces the MPEG stream which isdigital-recorded on the erasable video cassette tape 2, and outputs itto the copyright information detection unit 4. The copyright informationdetection unit 4 detects the copyright information of the MPEG streamoutputted from the digital signal playback unit 9, and judges whetherthe contents are copy-inhibited or not.

When the copyright information detection unit 4 judges that the contentson the video cassette tape 2 are copy-inhibited, the MPEG streamreproduced by the digital signal playback unit 9 is encrypted by theencryption unit 10, and the encrypted stream is temporarily stored inthe HDD 11. Further, the erasing unit 5 immediately erases the MPEGstream reproduced by the digital signal playback unit 9 from the videocassette tape 2.

After erasing the signal, the video cassette tape 2 is ejected from theplayback/recording apparatus 8, and the video cassette tape 7 isinserted in the playback/recording apparatus 8 (in FIG. 2, both of thecassette tapes 2 and 7 are shown for convenience in description). Then,the HDD 11 reads the MPEG stream which is temporarily stored, andoutputs it to the decryption unit 12. At this time, the HDD 11 outputsthe encrypted MPEG stream and, simultaneously, erases the data. Theencrypted MPEG stream outputted from the HDD 11 is decrypted by thedecryption unit 12, and the decrypted MPEG stream is digital-recorded onthe video cassette tape 7 in the digital signal recording unit 13.

As described above, in the playback/recording apparatus according to thesecond embodiment, when the copyright information of the contents whichare digital-recorded on the erasable video cassette tape 2 is“copy-inhibited”, the contents which include the copyright informationindicating “copy-inhibited” and are in the copy-inhibited state areerased from the video cassette tape 2 and, simultaneously, recorded onthe other video cassette tape 7. Therefore, the copy-inhibited contentswhich are digital-recorded on the video cassette tape 2 can betransferred to the other video cassette tape 7 while avoiding that thesame contents exist at the same time.

Hereinafter, a third embodiment of the present invention will bedescribed.

Initially, the structure of a playback/recording apparatus according tothe third embodiment will be described with reference to FIGS. 3 and 4.FIGS. 3 and 4 are block diagrams illustrating a playback/recordingapparatus according to the third embodiment. In FIGS. 3 and 4, theplayback/recording apparatus is composed of a playback/erasing apparatus8 a as a first apparatus which receives an instruction for transferringthe contents, from a remote controller 1 that is a transfer instructionmeans, a recording apparatus 8 b as a second apparatus, and atransmission cable 18 connecting these apparatuses 8 a and 8 b. Thefirst apparatus 8 a is composed of an erasable video cassette tape 2 onwhich contents are recorded, a copyright information detection unit 4,an erasing unit 5, a digital signal playback unit 9, an APS (analogprotection system) 14, and a first authentication unit 15. The secondapparatus 8 b is composed of a recording unit 6, a video cassette tape 7to which the contents are to be transferred, and a second authenticationunit 16. The same constituents as those of the above-describedembodiment are given the same reference numerals and, therefore,descriptions thereof will be omitted hereinafter.

The APS 14 comprises an MPEG decoder 14 a and an NTSC encoder 14 b,wherein the MPEG decoder 14 a MPEG-decodes an MPEG stream which isoutputted from the digital signal playback unit 9, and the NTSC encoder14 b generates an audio signal and an NTSC video signal to be outputted.

The transmission cable 18 is a cable for transmitting an analog audiosignal and an analog video signal.

The first authentication unit 15 and the second authentication unit 16exchange ID information through the transmission cable 18, therebyperforming mutual authentication. This mutual authentication is carriedout employing an existing bi-directional communication method which usesa vertical blanking period of a video signal. Each of the firstauthentication unit 15 and the second authentication unit 16 forms acode, transfers the code to the authentication unit on the other end,and receives a return code. When the return code is identical to anexpected code, the authentication unit recognizes that theauthentication unit on the other end is a unit to which the contents canbe transferred. Further, the first authentication unit 15 and the secondauthentication unit 16 also perform transmission and reception of themoved contents.

Next, the operation of the playback/recording apparatus according to thethird embodiment will be described.

When the first apparatus 8 a receives an instruction for transferringthe contents, from the remote controller 1, the first authenticationunit 15 and the second authentication unit 16 perform mutualauthentication through the transmission cable 18.

The digital signal playback unit 9 reads the MPEG stream which isdigital-recorded on the video cassette tape 2, and outputs it to thecopyright information detection unit 4. Then, the copyright informationdetection unit 4 detects the copyright information of the MPEG streamoutputted from the digital signal playback unit 9, and judges whetherthe contents are copy-inhibited or not.

When it is judged by the copyright information detection unit 4 that thecontents on the video cassette tape 2 are copy-inhibited, the MPEGstream read by the digital signal playback unit 9 is inputted to the APS14, and MPEG-decoded by the MPEG decoder 14 a, and encoded by the NTSCencoder 14 b, thereby obtaining an audio signal and an NTSC videosignal. At this time, the NTSC encoder 14 b subjects the video signal toanalog protection, and superimposes copy generation management system(CGMS) information on the 20th line of the video signal as shown inFIGS. 5( a) and 5(b) and, thereafter, outputs the video signal.

Hereinafter, a description will be given of the CGMS information to besuperimposed on the 20th line of the video signal in the NTSC encoder 14b according to the third embodiment, with reference to FIG. 5. FIG. 5 isa diagram illustrating the waveform of the CGMS information according tothe third embodiment. The CGMS information shown in FIG. 5( b) issuperimposed on the 20th line of the video signal shown in FIG. 5( a).Transfer information is newly defined in bits 12 and 13 of the CGMSinformation, and information indicating whether transfer of the contentsis to be permitted or not is assigned to the bit 12 while informationindicating whether the contents are being transferred or not is assignedto the bit 13.

Further, the erasing unit 5 erases the MPEG stream reproduced by thedigital signal playback unit 9 from the video cassette tape 2simultaneously with playback of the MPEG stream.

The video signal and audio signal generated by the APS 14 aretransferred to the second apparatus 8 b through the first authenticationunit 15 and the transmission cable 18. Thereafter, in the secondauthentication unit 16, the CGMS information superimposed on the videosignal is detected. When the transfer permission on the bit 12 of theCGMS information is “1”, i.e., “permitted” and the transfer informationon the bit 13 is “1”, i.e., “being transferred”, the CGMS information isrecorded on the video cassette tape 7 in the recording unit 6, in likemanner as described for the first embodiment. At the same time, therecording unit 6 records the CGMS information in which the bit 13 is“0”, i.e., the transfer information indicates only playback, on thevideo cassette tape 7, as well as the video signal and the audio signal.

As described above, in the playback/recording apparatus according to thethird embodiment, when the copyright information of the contents whichare digital-recorded on the erasable video cassette tape 2 is“copy-inhibited”, the contents which include the copyright informationindicating “copy-inhibited” and are in the copy-inhibited state areerased from the video cassette tape 2 and, simultaneously, the contentsare converted into an analog signal and transferred by using transferinformation or the like and, thereafter, the analog signal is recordedon the other video cassette tape 7. Thereby, the copy-inhibited contentswhich are digital-recorded on the video cassette tape 2 can betransferred as an analog signal to the other video cassette tape 7 whileavoiding that the same contents exist at the same time.

Further, since the authentication units are provided, the contentsrecorded on the storage medium can be transferred between pluralplayback/recording apparatuses.

While in this third embodiment the copy generation management system(CGMS) information is superimposed on the 20th line of the video signalby the APS 14, the CGMS information may be superimposed on any line aslong as it is in the vertical blanking period of the video signal.

Furthermore, while in this third embodiment transfer of thedigital-recorded contents is described, when transfer of analog-recordedcontents is carried out, the digital signal playback unit 9 should bereplaced with the playback unit 3 and the APS 14 is removed (not shown),whereby transfer of the analog-recorded contents is realized.

Hereinafter, a fourth embodiment of the present invention will bedescribed.

Initially, the structure of a playback/recording apparatus according tothe fourth embodiment will be described with reference to FIGS. 6 and 7.FIGS. 6 and 7 are block diagrams illustrating the playback/recordingapparatus according to the fourth embodiment. As shown in FIGS. 6 and 7,the playback/recording apparatus is composed of a playback/erasingapparatus 8 a which is a first apparatus receiving an instruction fortransferring contents, from a remote controller 1, a recording apparatus8 b as a second unit, and a transmission cable 22 connecting theseapparatuses 8 a and 8 b. The first apparatus 8 a is composed of anerasable video cassette tape 2 on which contents are recorded, acopyright information detection unit 4, an erasing unit 5, an MPEGcoding unit 19, an encryption unit 10, and a first authentication unit20. The second apparatus 8 b is composed of a second authentication unit21, a decryption unit 12, a digital signal recording unit 13, and avideo cassette tape 7 to which the contents are to be transferred. Thesame constituents as those of the above-described embodiment are giventhe same reference numerals, and descriptions thereof will be omittedhereinafter.

The MPEG coding unit 19 comprises an NTSC decoder 19 a, an MPEG CODEC 19b, and an HDD 11, wherein an audio signal and a video signal outputtedfrom the playback unit 3 are converted into digital data by the NTSCdecoder 19 a and, thereafter, the digital data is subjected to MPEGcompression by the MPEG CODEC 19 b and temporarily stored in the HDD 11for continuous and efficient transfer.

The encryption unit 10 encrypts the MPEG-compressed data outputted fromthe HDD 11, and outputs the data together with an encryption key to thetransmission cable 22. Further, the HDD 11 outputs thetemporarily-stored MPEG stream and, simultaneously, erases it.

The transmission cable 22 is a cable for digital signals, whichtransmits digital data.

The first authentication unit 20 and the second authentication unit 21perform mutual authentication through the transmission cable 22, andperform transfer of the contents when authentication is established. Themutual authentication is carried out in the same way as described forthe third embodiment.

Next, a description will be given of the operation of theplayback/recording apparatus according to the fourth embodiment.

When the first apparatus 8 a receives an instruction for transferringthe contents, from a remote controller 1, the first authentication unit20 and the second authentication unit 21 perform mutual authenticationthrough the transmission cable 22.

This mutual authentication is identical to that described for the thirdembodiment, and transfer of the contents is carried out whenauthentication is established.

The playback unit 3 reproduces the contents recorded on the erasablevideo cassette tape 2, and outputs the contents to the copyrightinformation detection unit 4. The copyright information detection unit 4judges whether the contents are copy-inhibited or not, in the same wayas described for the first embodiment.

When the copyright information detection unit 4 judges that the contentson the video cassette tape 2 are copy-inhibited, the video signal andthe audio signal reproduced in the playback unit 3 are outputted to theMPEG coding unit 19. In the MPEG coding unit 19, these signals areconverted into digital data, by the NTSC decoder 19 a, and the digitaldata are MPEG-compressed by the MPEG CODEC 19 b and temporarily storedin the HDD 11 for continuous and efficient transfer. The MPEG-compresseddata are encrypted by the encryption unit 10, and outputted togetherwith an encryption key. At this time, the HDD 11 outputs thetemporarily-stored MPEG-compressed data and, simultaneously, erases thedata.

Further, the erasing unit 5 erases the signal reproduced by the playbackunit 3, from the video cassette tape 2, simultaneously with playback ofthe signal.

The encrypted compressed data outputted from the encryption unit 10, andthe encryption key to be used for decrypting the data are transferredfrom the first authentication unit 20, through the transmission cable22, to the second authentication unit 21. The decryption unit 12decrypts the encrypted data on the basis of the encryption key, andoutputs the decrypted data to the digital signal recording unit 13. Theencryption by the encryption unit 10 and the decryption by thedecryption unit 12 are carried out employing existing methods.

The MPEG stream inputted to the digital signal recording unit 13 isdigital-recorded on the video cassette tape 7, in the same way asdescribed for the second embodiment.

By the way, the mutual authentication by the first authentication unit20 and the second authentication unit 21 is carried out even while thecontents are being transferred, and the transfer of the contents iscontinued when mutual authentication is established.

As described above, in the playback/recording apparatus according to thefourth embodiment, when the copyright information of the contents whichare analog-recorded on the erasable video cassette tape 2 is“copy-inhibited”, the contents which include the copyright informationindicating “copy-inhibited” and are in the copy-inhibited state areerased from the video cassette tape 2 and, simultaneously, the contentsare converted into a digital signal, and the digital signal is recordedon the other video cassette tape 7. Thereby, the copy-inhibited contentswhich are analog-recorded on the video cassette tape 2 can be convertedinto the digital signal and transferred to the other video cassette tape7, while avoiding that the same contents exist at the same time.

While in this fourth embodiment the encryption unit 10 outputs theencryption key, the encryption unit 10 may receive an encryption keywhich is generated by the decryption unit 12 and outputted through thetransmission cable 22, to encrypt the contents using the encryption key.

Hereinafter, a fifth embodiment of the present invention will bedescribed.

Initially, the structure of a playback/recording apparatus according tothe fifth embodiment will be described with reference to FIG. 8. FIG. 8is a block diagram illustrating a playback/recording apparatus accordingto the fifth embodiment. In FIG. 8, the playback/recording apparatus iscomposed of a playback/erasing apparatus 8 a which is a first apparatusreceiving an instruction for transferring contents, from a remotecontroller 1 that is a transfer instruction means, a recording apparatus8 b as a second unit, and a transmission cable 22 connecting theseapparatuses 8 a and 8 b. The first apparatus 8 a is composed of anerasable video cassette tape 2 on which contents are recorded, aplayback unit 3, a copyright information detection unit 4, an erasingunit 5, a compression unit 23, an encryption unit 10, and a firstauthentication unit 20. The second apparatus 8 b is composed of a secondauthentication unit 21, a decryption unit 12, a decompression unit 24, adigital signal recording unit 13, and a video cassette tape 7 to whichthe contents are to be transferred. The same constituents as those ofthe above-described embodiment are given the same reference numerals,and descriptions thereof will be omitted hereinafter.

The compression unit 23 compresses image data of the contents, andinserts additional information, such as copyright information andtransfer information, in an area obtained by the compression.

The decompression unit 24 decompresses the image data of the contentswhich are compressed by the compression unit 23, and outputs theoriginal image data before compression.

Hereinafter, a description will be given of an image data compressionmethod and an image data decompression method.

First of all, a compression method will be described. The compressionunit 23 performs compression as follows. In image data in which thetotal number of values to be used as pixel values of image data is lessthan the total number of values expressed by the number N of bits perpixel, i.e., in image data having values which are not used as pixelvalues, a certain value G is generated by arranging plural pixel valuesso as to have digits (the respective pixel values are made to have thesame number of digits by adding zero until reaching the maximum numberof digits N) and, among values (unused generated values) which includethe unused pixel values and are generated by arranging plural pixelvalues so as to have digits as mentioned above, the total number T ofunused generated values which are smaller than the generated value G issubtracted from the generated value G.

Hereinafter, the compression method will be described more specifically,taking an example. Initially, it is assumed that a pixel value isexpressed with two bits, and values to be actually used as pixel valuesare three values of 00, 01, 10 in binary notation, and image data Vhaving three pixels exists. Since each pixel of the image data V is 2bits, a value which is generated by arranging these three pixel valuesso as to have digits becomes image data of 6 bits. There is one valuewhich is not used as a pixel value in the image data V, and this valueis “11” in binary notation. Accordingly, when the image data V is 00,01, 10 in binary notation, there is one unused generated value (000011)which is smaller than the generated value 000110 of the image data V,and 000101 (=000110−000001) is obtained as new image data. Further, whenthe image data V is 00, 10, 10 in binary notation, there are two unusedgenerated values (000011 and 000111) which are smaller than thegenerated value 001010 of the image data V, and 001000 (=001010−000010)is obtained as new image data. Furthermore, when the image data V is 10,10, 10 in binary notation, i.e., when each pixel value is the maximumpixel value (10), since there are sixteen unused generated values whichare smaller than the generated value 101010 of the image data V, 011010(=101010−010000) is obtained as new image data. In this way, the 6-bitlong image data V is converted into new image data in which the mostsignificant bit is 0, whereby image data compressed to 5-bit length isobtained.

Next, a description will be given of the case where image data, which isbased on the NTSC system ITU-R601 standard, is expressed with 8 bits,with reference to FIGS. 9 and 10. FIG. 9 shows computational expressionsof data compression according to the fifth embodiment, and FIG. 10 is ablock diagram illustrating a playback/recording apparatus according tothe fifth embodiment. In this case, although luminance values can takeany value from 16 to 235 (220 levels of gradation) in decimal notation,16 is subtracted from all of the luminance values to simplifycompression, whereby the range of the luminance values becomes 0 to 210.The quantity of data to be compressed in this case is calculated byobtaining a maximum integer value among x that satisfies an inequality:720×log220 (720−x)×log256, considering that there are 256 values to beexpressed by 8 bits and the number of significant pixels per scanningline is 720, and the maximum integer value is 19. Accordingly, thesignificant 720 pixels per scanning line can be compressed to 701(=720−19) pieces of pixel data at maximum. Hereinafter, consideringfurther simplification of calculation, 720 pieces of pixel data arecompressed to 702 pieces of pixel data. In this case, data of 18 pixels(18 bytes) are reduced from data of 720 pixels (720 bytes), and this isequivalent to a reduction of 1 bit from 5 pixels (5 bytes=40 bits).Accordingly, compression may be carried out in units of 5 pixels.Assuming that 5 pixel values before compression is d1, d2, d3, d4, andd5, a generated value G1 of d1 to d5, the total number T1 of unusedgenerated values smaller than the generated value G1, and image data G2after compression are as shown in FIGS. 9( a), 9(b), and 9(c),respectively, Then, the construction for implementing the computationalexpressions shown in FIG. 9 becomes as shown in FIG. 10, and the blockdiagram shown in FIG. 10 exists in the compression unit 23, wherein 23 adenotes an image data separator, 23 b to 23 e denote multipliers, and 23f denotes an adder. The image data separator 23 a separates the imagedata G1 into the respective pixels to be output, and the multipliers 23b to 23 e perform multiplication by bit-shifting and addition of therespective pixel values. For example, as for D8h×d2, since D8h is11011000 in binary notation, the sum of a value obtained bybit-extending the d2 and shifting the extended d2 by 7 bits to the left,a value obtained by shifting it by 6 bits, a value obtained by shiftingit by 4 bits, and a value obtained by shifting it by 3 bits, isobtained. Other terms are calculated in like manner as described above,and the adder 23 f calculates the sum of the results to output the G2.In this way, the compressed data G2 is obtained. Since thesecalculations are carried out within a predetermined period of time,delays due to compression are not accumulated, and compression can becarried out in synchronization with the image data inputting speed. Asdescribed above, the image data (luminance data) based on the NTSCsystem ITU-R601 standard are compressed in units of 5 pixels.

Next, a general form of the above-described compression method will bedescribed. Assuming that the number of bits of each pixel is M, thenumber of values to be used actually is U (<the M-th power of 2), thenumber of data before compression is W1, and the number of data aftercompression is W2, the quantity of data to be reduced by compression isrepresented by an integer x that satisfies W1×logU (W1−x)×M×log2. FromW1 and x(=W1−W2), the number of pixels (or bits) to be a unit of datacompression is calculated, and bit-shifting by bit-extension andaddition are repeated to compress the data.

Next, the decompression method will be described. Decompression by thedecompression unit 24 is carried out by calculating the total number ofunused generated values which are smaller than the generated value G,i.e., the above-mentioned total number T, and then adding it to thegenerated value G.

Hereinafter, a description will be given of examples of computationalexpressions in the case where the data G2 compressed by the compressionunit 23 are decompressed, with reference to FIGS. 11 and 12. FIGS. 11(a) and 11(b) show computational expressions for performing decompressionof the compressed data G2. The respective quotients shown in FIG. 11( a)are added to the compressed data values G2 as shown in FIG. 11( b),thereby reproducing the pixel data G1 before compression. Theconstruction for implementing the computational expressions shown inFIG. 11 is shown in FIG. 12. The construction shown in FIG. 12 exists inthe decompression unit 24, wherein 24 a denotes a compressed datadecompression unit, 24 b to 24 e denote dividers, 24 f to 24 i denotemultipliers, and 24 j denotes an adder. The compressed datadecompression unit 24 a successively extracts the compressed data G2from the inputted compressed data sequence, and outputs the data G2.Each of the dividers 24 b and 24 e performs division using an existingmethod such as non-restoring division, and outputs a quotient. Further,each of the multipliers 24 f to 24 i performs multiplication, andoutputs a product. The adder 24 j calculates the sum of the outputs ofthe multipliers 24 f to 24 i, and outputs the G1. In this way, the dataG1 before compression by the compression unit 23 is obtained. Since theabove-mentioned calculations are carried out within a predeterminedperiod of time, delays due to decompression are not accumulated, anddecompression can be carried out in synchronization with the compressedimage data inputting speed.

Next, a general form of the decompression method will be described. Asdescribed above, it is assumed that the number of bits of each pixel isM, the number of values to be used actually is U (<the M-th power of 2),the number of data before compression is W1, and the number of dataafter compression is W2. In this case, the W1 is the sum of the W2 and avalue which is obtained by adding the following quotients: a quotientobtained by dividing the W2 with U, a quotient obtained by dividing thequotient with U, a quotient obtained by dividing the quotient with U, .. . which are repeated by the number of times equal to the number ofpixels in each compression unit (in this case, 5)−1 (in the case, 4).Thus, data decompression can be performed by repeating bit-shifting andaddition. Further, 16, which has been reduced before compression tosimplify compression in the compression unit 23, is added to each pixelvalue of the decompressed image data G1, thereby outputting the originalimage data.

It is needless to say that the above-described compression anddecompression methods can be performed on color-difference data and,further, they are also applicable to digital data other than image data.

Next, the operation of the playback/recording apparatus according to thefifth embodiment will be described.

When the first apparatus 8 a receives an instruction for transferringthe contents, from the remote controller 1, the first authenticationunit 20 and the second authentication unit 21 perform mutualauthentication through the transmission cable 22. This mutualauthentication is identical to that described for the third embodiment,and transfer of the contents is carried out when authentication isestablished.

The playback unit 3 reproduces the contents recorded on the erasablevideo cassette tape 2, and outputs it to the copyright informationdetection unit 4. The copyright information detection unit 4 detectswhether the contents are copy-inhibited or not.

When the copyright information detection unit 4 detects that thecontents on the video cassette tape 2 are copy-inhibited, the contentsreproduced by the playback unit 3 are outputted to the compression unit23. In the compression unit 23, the image data of the contents arecompressed by the above-mentioned compression method, and additionalinformation such as copyright information and transfer information isinserted in an area secured by the compression. Thereafter, the data ofthe contents are outputted to the encryption unit 10 and encrypted.Although it is not shown in FIG. 6, a temporary storage unit fortemporarily storing the contents data may be provided for continuous andefficient transfer of the contents.

Then, in the erasing unit 5, the contents on the video cassette tape 2reproduced by the playback unit 3 are erased.

The first authentication unit 20 digital-transfers the encryptedcontents data, together with the encryption key and the additionalinformation, through the transmission cable 22 to the second apparatus 8b. The second authentication unit 21 detects the additional informationand outputs it, and the second apparatus 8 b continues transfer of thecontents when it receives the transfer information included in theadditional information. The encrypted contents data transferred to thesecond apparatus 8 b are decrypted by the decryption unit 12 on thebasis of the encryption key. Further, information as to whether thecontents data are compressed by the compression unit 23 or not is alsotransferred. When the contents data are compressed, the compressed dataare decompressed by the decompression unit 24 using the above-mentioneddecompression method, and the decompressed contents are digital-recordedon the video cassette tape 7.

As described above, in the playback/recording apparatus according to thefifth embodiment, when the copyright information of the contents whichinclude image data and are recorded on the erasable video cassette tape2 is “copy-inhibited”, the contents including the copyright informationindicating “copy-inhibited” and being in the copy-inhibited state areerased from the video cassette tape 2 and, simultaneously, the imagedata are compressed to secure an area where the additional informationis to be inserted and, thereafter, the image data are decompressed andrecorded on the other video cassette tape 7. Therefore, thecopy-inhibited contents recorded on the video cassette tape 2 can betransferred to the other video cassette tape 7 while avoiding that thesame contents exist at the same time.

Hereinafter, a sixth embodiment of the present invention will bedescribed.

Initially, the structure of a playback/recording apparatus according tothe sixth embodiment will be described with reference to FIG. 13. FIG.13 is a block diagram of a playback/recording apparatus according to thesixth embodiment, and the constituents overlapping those of theabove-mentioned embodiment with respect to transfer of contents areomitted. In FIG. 13, the playback/recording apparatus is composed of aplayback/erasing apparatus 8 a which is a first apparatus receiving aninstruction for transferring contents, from a remote controller 1 thatis a transfer instruction means, a recording apparatus 8 b as a secondunit, and a transmission cable 22 connecting these apparatuses 8 a and 8b. The first apparatus 8 a is composed of an erasable video cassettetape 2 on which contents are recorded, a playback unit 3, an erasingunit 5, a first control unit 25, and a first authentication unit 20. Thesecond apparatus 8 b is composed of a second authentication unit 21, asecond control unit 26, a recording unit 27 for recording a digitalsignal on a magneto-optic disk, a playback unit 28 for reproducing adigital signal from a magneto-optic disk, and a magneto-optic disk 29 towhich the contents of the video cassette tape 2 are to be transferred.The same constituents as those of the above-described embodiment aregiven the same reference numerals, and descriptions thereof will beomitted hereinafter.

The digital signal recording unit 27 records data of the transferredcontents on the magneto-optic disk 29.

The digital signal playback unit 28 reproduces the data of the contentsrecorded on the magneto-optic disk 29.

The first controller 25 controls the contents transfer process in thefirst apparatus 8 a.

The second controller 26 outputs a result of comparison between therecorded data obtained by the digital signal recording unit 27 and thereproduced data obtained by the digital signal playback unit 28, andcontrols the contents transfer process in the second apparatus 8 b.

Next, the operation of the playback/recording apparatus according to thesixth embodiment will be described.

When the first apparatus 8 a receives an instruction for transferringthe contents, from the remote controller 1, the first authenticationunit 20 and the second authentication unit 21 perform mutualauthentication. When it is detected that the contents on the videocassette tape 2 is copy-inhibited, the contents reproduced by theplayback unit 3 are converted into digital data or the like, anddigital-transferred through the transmission cable 22 to the secondapparatus 8 b. Further, the contents reproduced by the playback unit 3are erased in the erasing unit 5.

The digital signal recording unit 27 digital-records the data. of thetransferred contents on the magneto-optic disk 29, and the digitalsignal playback unit 28 reproduces the digital-recorded data. The secondcontrol unit 26 performs comparison between the reproduced data obtainedby the digital signal playback unit 28 and the recorded data obtained bythe digital signal recording unit 27, and outputs a result. Based on theresult of the data comparison, when the reproduced data are equal to therecorded data, recording on the magneto-optic disk 29 by the digitalsignal recording unit 27 is continued. When the reproduced data are notequal to the recorded data, the second control unit 26 stops thetransfer process of the second apparatus 8 b, and outputs, as thetransfer information, occurrence of mismatch and its positionalinformation to the second authentication unit 21. The transferinformation is notified through the first authentication unit 20 to thefirst control unit 25, and the first control unit 25 stops the transferprocess of the first apparatus 8 a. Thereafter, transfer of the contentsis resumed from the position where data recording by the digital signalrecording unit 27 was not performed normally, whereby the contentsrecorded on the video cassette tape 2 can be normally recorded on thevideo cassette tape 7.

Further, when transferring contents of about two hours which arerecorded on the video cassette tape 2, in order to perform efficienttransfer, the contents to be transferred are divided in units of, forexample, 10 seconds, as an insurance against sudden power-off of theplayback/recording apparatus, and the divided contents are continuouslytransferred. Thereby, stable transfer of contents is achieved. Further,when the above-mentioned resumption of transfer is started from aboundary of the divided contents, stable transfer of contents isrealized.

With respect to the division of contents, the playback/recordingapparatus of the present invention performs the division of contents bycounting a predetermined number of data, employing a clock which is usedfor another digital processing, time counting, or the like. Further, asfor the clock, a clock possessed by each of the first and secondapparatuses 8 a and 8 b may be employed and, even when these clocks havedifference frequencies, there occurs no problem because each of theapparatus 8 a and 8 b counts the number of contents data in itself.Accordingly, the second apparatus 8 b successively transfers the sectionnumbers recorded in the digital signal recording unit 27 (e.g.,successively assigned count values) as the transfer information to thefirst apparatus 8 a through the first authentication unit 20 and thesecond authentication unit 21. On receipt of the section information,the first apparatus 8 a reproduces the next contents section and outputsit, whereby transfer of the contents can be reliably carried out inunits of sections.

Further, in the case where the source of the contents, i.e., the firststorage medium, is a storage medium such as a magneto-optic disk, amagnetic disk, or an optical disk (not shown), when the contents aretransferred in byte units, the recording position at the destination andthe erasing position in the transferred contents can be made the same,whereby transfer of copy-inhibited contents such as a still picture canbe carried out appropriately.

Further, information indicating, as contents information, whethertransfer of contents is permitted or not may be recorded in the storagemedium as a part of copyright information, and this transferpermission/inhibition information may be detected by the copyrightinformation detection unit 4 or the like which is described for theabove embodiment, whereby transfer of contents can be controlled on thebasis of this information.

Furthermore, information indicating, as contents information, whether ornot transfer is to be permitted even when the type of the storage medium(tape, disk, or the like) or the recording mode (digital or analog)differs between the source of the contents and the destination of thecontents, may be added as a part of copyright information, or it may benewly assigned to a reservation bit or the like of the CGMS which isdescribed for the third embodiment, whereby a restriction can be placedon transfer of contents, and transfer of contents can be controlled onthe basis of the contents information by detecting the information withthe copyright information detection unit 4 or the like which isdescribed for the above embodiment.

Furthermore, the contents to be transferred may be already-encryptedcontents.

While in this sixth embodiment transfer of contents between twoapparatuses which have performed mutual authentication is described,transfer of contents can be carried out similarly also in aplayback/recording apparatus where playback, erasing, and recordingmeans exist in a single unit.

As described above, the playback/recording apparatus according to thesixth embodiment can perform transfer of contents with stability.

Next, a seventh embodiment of the present invention will be described.

Initially, the structure of a playback/recording apparatus according tothe seventh embodiment will be described with reference to FIG. 14. FIG.14 is a block diagram illustrating a playback/recording apparatusaccording to the seventh embodiment, wherein the constituentsoverlapping those of the above-mentioned embodiment with respect totransfer of contents are omitted. In FIG. 14, a playback/recordingapparatus 8 according to the seventh embodiment is composed of a CPU 30,a nonvolatile memory 31, and a display panel 32. When the apparatus 8receives an instruction for transferring contents, from a remotecontroller 1 that is a move instruction means, it transfers the contentsfrom an erasable storage medium to another storage medium. The sameconstituents as those of the above-described embodiment are given thesame reference numerals, and descriptions thereof will be omittedhereinafter.

The CPU 30 records information indicating transfer of the contents onthe nonvolatile memory 31 and, simultaneously, erases the information.

The nonvolatile memory 31 holds information relating to transfer ofcontents, such as the transfer information, copyright information,information indicating division of contents, and the like.

The display panel 32 displays the transfer status of the contents to theoutside of the apparatus.

Next, the operation of the playback/recording apparatus according to theseventh embodiment will be described.

When the playback/recording apparatus 8 receives an instruction fortransferring the contents, from the remote controller 1, the CPU 30stores the information indicating transfer of the contents in thenonvolatile memory 31, and erases the information from the nonvolatilememory 31 when transfer of the contents is ended. Further, while thecontents are being transferred, the display panel 32 displays that thecontents are being transferred, to the outside of the apparatus.

While in this seventh embodiment a playback/recording apparatus havingplayback, erasing, and recording means in a single unit is described,transfer of contents can be carried out similarly also in aplayback/recording apparatus having a first apparatus and a secondapparatus.

As described above, in the playback/recording apparatus according to theseventh embodiment, even when transfer of contents is interrupted due topower-off of the playback/recording apparatus or the like while thecontents are being transferred, the transfer information can be obtainedby accessing the nonvolatile memory 31 when the power is turned onagain, whereby the transfer of contents can be removed and continued.Further, when the contents are being transferred, a message indicatingthe transfer is displayed on the display panel, thereby notifying theviewer that the contents are being transferred.

1. A playback/recording apparatus for performing transfer of contentsrecorded on an erasable storage medium, between apparatuses: saidplayback/recording apparatus comprising a playback/erasing apparatus asa first apparatus, a recording apparatus as a second apparatus, and atransmission line such as a transmission cable or the like forconnecting the first and second apparatuses; said first apparatuscomprising: a first authentication means for performing mutualauthentication and transfer of contents between itself and the secondapparatus; a playback means for reproducing contents recorded on a firststorage medium, and outputting the reproduced contents; a detectionmeans for detecting copyright information of the contents; an erasingmeans for erasing the contents from the first storage medium; and anencryption means for encrypting the output from the playback means, andoutputting the encrypted data; and said second apparatus comprising: asecond authentication means for performing mutual authentication andtransfer of contents between itself and the first apparatus; adecryption means for decrypting the encrypted data; and a recordingmeans for recording the contents on a second storage means; wherein,when performing transfer of the contents, mutual authentication iscarried out between the first authentication means and the secondauthentication means, the contents are reproduced by the playback meansand outputted and, when the output of the detection means indicates thatthe contents are copy-inhibited, data of the contents are encrypted bythe encryption means and outputted, the contents are erased from thefirst storage medium by the erasing means, the encrypted data aredecrypted by the decryption means and outputted, and the contents arerecorded on the second storage means by the recording means, therebytransferring the contents.
 2. The playback/recording apparatus definedin claim 1, further comprising a temporary storage means for temporarilystoring the contents; wherein the contents are temporarily stored in thetemporary storage means.
 3. A playback/erasing apparatus as a firstapparatus, which is one of components of a playback/recording apparatusfor performing transfer of contents recorded on an erasable storagemedium, between the first apparatus and a second apparatus, comprising:a first authentication means for performing mutual authentication andtransfer of contents between itself and the second apparatus; a playbackmeans for reproducing contents recorded on a first storage medium, andoutputting the reproduced contents; a detection means for detectingcopyright information of the contents; and an erasing means for erasingthe contents from the first storage medium; wherein, when performingtransfer of the contents, mutual authentication is carried out betweenthe first authentication means and the second apparatus, and thecontents are reproduced by the playback means and outputted and, whenthe output of the detection means indicates that the contents arecopy-inhibited, the contents are erased from the first storage medium bythe erasing means.
 4. The playback/erasing apparatus as the firstapparatus defined in claim 3, further comprising a first control meansfor controlling the playback means and the erasing means; wherein theplayback means and the erasing means are controlled by the first controlmeans, thereby performing transfer of the contents.
 5. Theplayback/erasing apparatus as the first apparatus defined in claim 3,wherein mutual authentication by the first authentication means is alsocarried out during transfer of the contents, and the transfer of thecontents is continued when mutual authentication is established.
 6. Theplayback/erasing apparatus as the first apparatus defined in claim 3,further comprising a transfer instruction means for sending aninstruction for transferring the contents, to the first apparatus;wherein transfer of the contents is carried out according to theinstruction of the transfer instruction means.
 7. A playback/erasingapparatus as a first apparatus, which is one of components of aplayback/recording apparatus for performing transfer of contentsrecorded on an erasable storage medium, between the first apparatus anda second apparatus, comprising: a first authentication means forperforming mutual authentication and transfer of contents between itselfand the second apparatus; a playback means for reproducing contentsrecorded on a first storage medium, and outputting the reproducedcontents; a detection means for detecting copyright information of thecontents; an erasing means for erasing the contents from the firststorage medium; and an encryption means for encrypting the output of theplayback means, and outputting the encrypted data; wherein, whenperforming transfer of the contents, mutual authentication is carriedout between the first authentication means and the second apparatus, andthe contents are reproduced by the playback means and outputted and,when the output of the detection means indicates that the contents arecopy-inhibited, the data of the contents are encrypted by the encryptionmeans and outputted, and the contents are erased from the first storagemedium by the erasing means.
 8. The playback/erasing apparatus as thefirst apparatus defined in claim 7, further comprising a temporarystorage means for temporarily storing the contents; wherein the contentsare temporarily stored in the temporary storage means.